1. Field of the Invention
The present invention relates to a fluid device such as a pump, a valve, or an accumulator and a fitting for a tube, a pipe, or the like, and more particularly to a connecting structure between the fluid device and the fitting in which a peripheral portion of a fluid supply/discharge passage in the fluid device, and the fitting are fittingly coupled to each other, whereby the supply/discharge passage and a passage formed in the fitting are communicatingly connected to each other.
2. Description of the Prior Art
In a fluid system for transporting chemical liquid for washing or the like used in a semiconductor or liquid crystal panel production apparatus, for example, a filter is often disposed on the upstream side of a pump in the liquid transporting direction in order to prevent a foreign substance entering the a fluid passage for washing liquid, chemical liquid, or the like, from entering the interior of the pump to cause a fault or a damage.
As an example of such a prior art, a chemical liquid supply system 25 disclosed in Japanese kokai 2006-49756 is known. In FIG. 1 of JP2006-49756, it will be understood that the reference numeral 14 indicates a filter, and the filter is placed on the upstream side of a pump indicated by the reference numeral 11 in the liquid transporting direction.
In the case where a filter is disposed as an independent device in a fluid supply system as in the above-described prior art, an installation space for the filter is required, and there arises a disadvantage that the size of the system is correspondingly increased. In replacement due to the end of the life or the like, moreover, the filter is often replaced in the form of assembly replacement, and hence there is another disadvantage that this influences the running cost at an unnegligible degree.
In a fluid supply system, there is always a fear of leakage from a connecting portion. In a configuration where a filter exists as one component, a connecting portion with respect to a pipe or the like is required in each of supply/discharge ports of the filter. Accordingly, there is a further disadvantage that potential sites of leakage at connections are increased.
In the invention, attention is focused on the connecting structure between a fitting and a fluid device in a fluid system such as the above-described chemical liquid supply system, or an apparatus, and the structure is improved. It is an object of the invention to provide a connecting structure between a fluid device and a fitting in which a functional component such as a filter is integrally attached to a connecting portion to solve the above-discussed problems as far as possible.